Time: 946 AM Fri July 29, 2022 Forecaster: Laura Smith ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- AFTERNOON THUNDERSTORMS LIKELY TODAY/HEAVY RAINFALL THREAT CONTINUES - A saturated column is in place over the District this morning with surface dewpoints in the mid 50s to around 60 degrees expected today. In addition to abundant moisture, a Denver Cyclone and accompanying surface boundary at the DCVZ have been steadily developing throughout the morning. Storm motions will be slower today; ESE at 10-15 mph. These conditions favor thunderstorms capable of producing up to 1.0"-2.0" of heavy rain fall in 10-30 minutes. Hail is also possible. - Like yesterday, cloud cover may prevent radiational warming, inhibiting storm development across the lower elevations. However, current observations show the stratus deck across the District is already starting to erode. Convective temperature is around 85 degrees today, which should be reached if clouds continue to dissipate. - Storms will initiate across higher terrain between noon and 2PM, moving into the District by 3PM. Outflow boundaries will trigger clusters of storms that will slowly propagate east and anchor to the convergence boundary on the eastern side of the District. Prime time is between 3pm and 7pm, with a small chance an isolated shower or two is kicked up via outflow boundary from storms on the convergence line after 7pm. Storm activity is not expected overnight or tomorrow morning. STORM RAINFALL POTENTIAL AND DURATION: Weak thunderstorms will produce 0.3-1.0" in 10-30 minutes. Moderate to strong thunderstorms will have the potential to produce 1.0-2.0" in 10-30 minutes. WORST CASE SCENARIO: A strong anchored thunderstorm or a slower moving large thunderstorm may result in rainfall rates up to 3.0" in 45-75 minutes. A LOOK AHEAD: High pressure ridging continues across the intermountain west, transporting monsoonal moisture into the state through the weekend. Conditions across the state will begin drying tomorrow. Afternoon showers and thunderstorms will be isolated and relatively light. Highs will be in the upper 80s to around 90 degrees. Sunday will be similar with highs in the upper 80s to low 90s and a slight chance for isolated afternoon thunderstorms. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 100 PM TO 800 PM 0.3" (60%) to 1.0" (30%) to 2.0" (15%) MOD Arapahoe 100 PM TO 800 PM 0.3" (60%) to 1.0" (30%) to 2.0" (15%) MOD Boulder 100 PM TO 800 PM 0.3" (60%) to 1.0" (30%) to 2.0" (15%) MOD Broomfield 100 PM TO 800 PM 0.3" (60%) to 1.0" (30%) to 2.0" (15%) MOD Denver 100 PM TO 800 PM 0.3" (60%) to 1.0" (30%) to 2.0" (15%) MOD Douglas 100 PM TO 800 PM 0.3" (60%) to 1.0" (30%) to 2.0" (15%) MOD Jefferson 100 PM TO 800 PM 0.3" (60%) to 1.0" (30%) to 2.0" (15%) MOD Foothills above 6500ft       Boulder 100 PM TO 800 PM 0.3" (90%) to 1.0" (60%) to 2.0" (30%) HIGH Douglas 100 PM TO 800 PM 0.3" (90%) to 1.0" (60%) to 2.0" (30%) HIGH Jefferson 100 PM TO 800 PM 0.3" (90%) to 1.0" (60%) to 2.0" (30%) HIGH MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]